svn commit: r209116 - head/sys/dev/cxgb

[Lawrence Stewart]

Hi Navdeep,

On 06/13/10 08:33, Navdeep Parhar wrote:
> Log:
>    cxgb(4): add knob to get packet timestamps from the hardware.
>
>    The T3 ASIC can provide an incoming packet's timestamp instead of its RSS hash.
>    The timestamp is just a counter running off the card's clock.  With a 175MHz
>    clock an increment represents ~5.7ns and the 32 bit value wraps around in ~25s.
>
>    # sysctl -d dev.cxgbc.0.pkt_timestamp
>    dev.cxgbc.0.pkt_timestamp: provide packet timestamp instead of connection hash
>
>    # sysctl -d dev.cxgbc.0.core_clock
>    dev.cxgbc.0.core_clock: core clock frequency (in KHz)
>    # sysctl dev.cxgbc.0.core_clock
>    dev.cxgbc.0.core_clock: 175000

Is this really a "one or the other" feature, or is it technically 
possible to support both simultaneously at some point in the future if 
additional work was done?

Just curious...

Cheers,
Lawrence